Headbox for cylinder roll papermaking machine

ABSTRACT

A headbox is disclosed having vertical flow chamber connected to a curved a tapered nozzle which defines a slice opening for jetting paper stock from the flow chamber along a that having both horizontal and vertical components and into a nip above a cylindrical forming roll and beneath a felt tangentially engaging an upper portion of the forming roll. The headbox nozzle has an upper and lower lip projecting into the nip. an adjusting mechanism is provided for the upper lip which includes a plurality of adjusting arms each connected on one end to the top of the upper lip proximate to the slice opening. the arm projects from the slice opening toward the flow chamber end of the nozzle and diverges from the upper lip to define a generally wedge-shaped space between the arm and the upperlip. A horizontal pivot is connected to the arm intermediate the ends thereof. A journal is connected to the pivot and has a like portion which spans the space between the adjusting arm and the upper lip and is connected to the upper lip. The adjusting arm is made up of a first and a second section pivotally connected by a horizontal pin at a location between the journal and the flow chamber end of the adjusting arm. The section that comprises the slice opening end of the arm has a portion projecting around the pin with a terminal end of this portion vertically spaced above the other of the section. A vertically adjustable link connects this terminal end portion of the one section, to said other of the section, to said other of the section, to provide for holding the two sections of each arm in variable preselected angular positions relative to each other for warping the upper slice lip to provide a desired profile to the upper lip. A horizontal rotatable drive shaft is mounted on the headbox adjacent the flow chamber end of the adjusting arm and this shaft has a horizontal pin attached to the periphery of the shaft which projects into a slot defined in the adjacent end which projects into a slot defined in the adjacent end of the arm. Rotation of the drive shaft raises and lowers the connected end of the adjusting arm about the pivot and bends the upper lip to vertically adjust the position of the slice opening end of the upper lip relative to the lower lip.

May 22, 973 D, Rl CURIT|5 3,734,821

HEADBOX FOR CYLINDER ROLL PAPERMAKING MACHINE Filed Dec. 14, 1970 @Mmm/w United States Patent O M s 734,821 nnanox rok CYLIDER RoLL PAPERMAKING MACHINE Donald R. Curtis, Appleton, Wis., assiguor to Allis- Chalmers Manufacturing Company, Milwaukee, Wis. Filed Dec. 14, 1970, Ser. No. 97,607 Int. Cl. D21f 1/04 U.S. Cl. 162-317 5 Claims ABSTRACT F THE DISCLOSURE A headbox is disclosed having a vertical flow chamber connected to a curved and tapered nozzle which defines a slice opening for jetting paper stock from the flow chamber along a path having both lhorizontal and vertical components and into a nip above a cylindrical forming roll and beneath a felt tangentially engaging an upper portion of the forming roll. The headbox nozzle has an upper and lower lip projecting into the nip. An adjusting mechanism is provided for the upper lip which includes a plurality of adjusting arms each connected on one end to the top of the upper lip proximate to the slice opening. The arm projects from the slice opening toward the flow lchamber end of the nozzle and diverges from the upper lip to define a generally wedge-shaped space between the arm and the upper lip. A horizontal pivot is connected to the arm intermediate the ends thereof. A journal is connected to the pivot and has a link portion which spans the space between the adjusting arm and the upper lip and is connected to the upper lip. The adjusting arm is made up of a first and a second section pivotally connected by a horizontal pin at a location between the journal and the iloW chamber end of the adjusting arm. The section that comprises the slice opening end of the arm has a portion projecting around the pin with a terminal end of this portion vertically spaced above the other of the sections. A vertically adjustable link connects this terminal end portion of the one section, to said other of the sections, to provide for holding the two sections of `each arm in variable preselected angular positions relative to each other for warping the upper slice lip to provide a desired prole to the upper lip. A horizontal rotatable drive shaft is mounted on the headbox adjacent the :Flow chamber end of the adjusting arm and this shaft has a horizontal pin attached to the periphery of the shaft which projects into a slot defined in the adjacent end of the arm. Rotation of the drive shaft raises and lowers the connected end of the adjusting arm about the pivot and bends the upper lip to vertically adjust the position of the slice opening end of the upper lip relative to the lower lip.

BACKGROUND OF THE INVENTION Field of the invention This invention relates to a papermaking machine in which pulp stock is directed by a headbox in a generally tangential direction at a forming roll, and in particular to a headbox for such a machine and having an adjustable slice opening control.

Description of the prior art 'Prior art patents relating to web formation on forming rolls indicate that perhaps the rst type, and apparently the earliest of such machines to be developed, involved a pervious cylinder (sometimes called a cylinder mold) that rotated partly submerged in a vat containing pulp, and a layer of pulp was brought up from the vat on the revolving mold. U.S. patents that illustrate typical machines of that type include U.S. 206,106 and U .S. 206,107 of 18718; and US. 1,578,729 of 1926.

Patented May 22, 1973 ICC The seconds, and apparently next type of such machine to appear, involves a pervious cylinder with paper stock jetted thereon from a headbox such as had been developed for Fourdrinier machines. U.S. Pat. 1,856,081 of 1932 (see FIG. 4) discloses such a machine.

A third type of such machine involves a pervious cylinder part of which is lapped by a felt belt in contact with part, but not all, of the outer surface of the cylinder and a headbox that jets paper stock upwardly onto the upwardly turning side of the cylinder and beneath the felt belt where a web of paper is formed. The newly formed web is lifted olf of the cylinder by the felt as the felt is lifted off the cylinder. Patents that illustrate typical machines of that type include U.S. 2,162,097 of 1939; U.S. 2,934,140 of 1960 and U.S. 3,252,853 of 1966.

SUMMARY lOF THE INVENTION The present invention relates to a headbox for the `aforesaid third type of machine for forming paper on a cylindrical web forming roll.

It is an obje'ct lof the present invention to provide a headbox for such machines, which is provided with a stock discharge nozzle having an upper and lower lip that in vertical cross section define a thin wedge leading to a slice opening, for projecting into a small angle nip of a felt lapping a forming roll, and a new and improved low profile adjusting mechanism for the upper lip arranged along the top of and to the rear of the upper lip to provide a minimum interference to locating the nozzle close to the nip between the felt and the forming roll.

According to a preferred embodiment of the present invention a headbox is provided with a vertical ow chamber connected to a curved and tapered nozzle which defines a slice opening for jetting paper stock from the flow chamber along a path having both horizontal and vertical components and into a nip above a cylindrical forming roll and beneath a felt tangentialy engaging an upper portion of the forming roll. The headbox nozzle has an upper and lower lip projecting into the nip. An adjusting mechanism is provided for the upper lip which includes a plurality of adjusting arms each connected on one end to the top of the upper lip proximate to the slice opening. The arm projects from the slice opening toward the flow chamber end of the nozzle and diverges from the upper lip to dene a generally wedge-shaped space between the arm and the upper lip. A horizontal pivot is connected to the arm intermediate the ends thereof. A journal is connected to the pivot and has a link portion which spans the space between the adjusting arm and the upper lip and is connected to the upper lip. A horizontal rotatable drive shaft is mounted on the headbox adjacent the How chamber end of the adjusting arm and this shaft has a horizontal pin attached to the periphery of the shaft which projects into a slot defined in the adjacent end of the arm. Rotation of the drive shaft raises and lowers the connected end of the adjusting arm about the pivot and bends the upper lip to vertically adjust the position of the slice opening end of the upper lip relative to the lower lip.

Because the pivot about which the adjusting arm turns is spaced Well to the rear of the slice opening, and the drive shaft means is even farther to the rear, the nozzle and adjusting arm can be made with a very low prole and small angle taper (as appears in vertical cross section) and the nozzle therefore may be inserted deep within a small angle nip and close to the location Where the felt comes in contact With the forming cylinder.

According to another feature of the invention the adjusting arm is made up of a rst and a second section pivotally connected by a horizontal pin at a location between the journal and the ow chamber end of the adjusting arm. The section that comprises the slice opening end of the arm has a portion projecting around the pin with a terminal end of this portion vertically spaced above the other of the sections. A vertically adjustable link connects this terminal end portion of the one section, to said other of the sections, to provide for holding the two sections of each arm in variable preselected angular positions relative to each other for warping the upper lip to provide the upper lip with a desired profile.

Other features and objects of the invention that have been attained will appear from the more detailed description to follow with reference to an embodiment of the present invention shown in the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. l of the accompanying drawing shows diagrammatically a side elevation, partly in section, a papermaking machine with headboxes according to the present invention; and

FIG. 2 is an enlarged fragmentary View partially in section of a portion of such a headbox.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring t FIG. 1 of the drawing, a portion of a papermaking machine is shown for forming fiber and water pulp into a Web of heavy paper, paperboard or multilayer paper. A first stage web forming unit 1 is provided for forming an initial Web W, and a Ifinal stage forming unit 2 is provided for depositing a final layer of pulp beneath a wet web formed in such as the first stage forming unit 1. In a commercial installation several intermediate stage forming units (not shown) may be arranged in series between the first and final stage units here identified with the reference numerals 1 and 2. A typical commercial installation may have seven stages each comprising a forming unit substantially identical to the units 1, 2 shown in the drawing. At the web Outrun end of the final stage forming unit 2, a pickup press 3 is provided to pickup and transport the web W to a press section and drying section of the papermaking machine (not shown), both of which may be of conventional design and construction for heavy or multilayer paper such as will be formed by a series of forming units such as the units 1, 2.

Referring to the lfirst stage web forming unit 1 shown in FIG. l, a headbox 5 is provided with a slice opening 6 for discharging and directing paper stock along a generally tangential path toward a top portion of a forming roll 7 which rotates in the direction indicated by an arrow. An endless loop fabric (felt) belt 8 is arranged and guided by a turning roll 9 upstream of headbox 5 and a pickup roll 10 downstream of headbox 5 to lap the top and part of the down turning side of forming roll 7. The belt 8 extends through each forming unit and at the pickup press 3 turns and is guided by one or more turning rolls 11 back to the first stage unit. The pickup roll 10 of unit 1, a pickup roll 10a of unit 2 and pickup rolls for units intermediate units 1 and 2 (and not shown) are all therefore within the continuous and endless loop of the belt 8.

The headbox 5 is provided with a stock entrance manifold 15 and a plurality of tubes 16 connecting manifold 15 to a vertical flow chamber 17. One or more hollow perforated distributor rolls 18 may be provided in liow chamber 17. The vertical flow chamber 17 is connected to a curved and tapered nozzle 20 which defines the slice opening 6 for jetting paper stock from the flow chamber 17 along a path having both horizontal and vertical components and into a nip N above the uylindrical forming roll 7 and beneath the felt 8 trangentially engaging the upper portion of the forming roll 7.

Referring to FIG. 2, the headbox nozzle 20 has an upper lip 21 and lower lip 22 projecting into the nip N. A polyethylene strip 22a may be attached to the lower surface of lip 22. An adjusting mechanism 25 is provided for the upper lip 21 which includes a plurality of adjusting arms 26 each connected on one end 27 to the top of the upper lip 21 proximate to the slice opening 6. The arm 26 projects from the slice opening 6 back toward the ow chamber 17 and diverges from the upper lip 21 to define a generally wedge-shaped space 30 between the arm 26 and the upper lip 21. A horizontal pivot 31 is connected to the arm 26 intermediate the ends thereof. A journal 32 is connected to the pivot 31 and has a link portion 33 which spans the space 30 between the adjusting arm 26 and the upper lip 21 and is connected to the upper lip 21. The adjusting arm 26 is made up of a first section 26a and a second section 26b pivotally connected by a horizontal pin 35 at a location between the journal 32 and the ow chamber end of the adjusting arm 26. The section 26a, that comprises the slice opening end of the arm 26, has a portion 26a-a projecting around the pin 35 with a terminal end 36 of this portion 26a-a vertically spaced above the other of the sections 26b. A vertically adjustable link 40 connects this terminal end 36 of the one section 26a-a, to said other of the sections 26b, to provide for holding the two sections 26a, 26b of each arm 26 in variable preselected angular positions relative to each other.

'Ihe link 40 is shown projecting vertically through a hole 41 in the terminal end portion 26a-a. The link 40 is threaded to engage a holding nut 42 beneath the terminal end portion 26a-a and a holding nut 43 above terminal end portion 26a-a. The nuts 42, 43 hold the section 26a-a of arm 26 in selected angular positions relative to the section 26b of arm 26.

A horizontal rotatable drive shaft 50 is journaled in a bracket 51 carried by a portion y52 of headbox 5 to the rear of nozzle 20. The shaft 50 has a horizontal pin 53 attached to the periphery of the shaft 50 to span a slot opening 50a in shaft 50. Pin 53 projects into a slot 54 defined in the adjacent end 0f the arm 26b and the end of arm 26 defining slot 54 projects through slot 50a and into shaft 50. Referring to FIG. l1 and headbox 5a of unit 2, a crank lever 55 is connected to the end of drive shaft 50. A jack screw assembly 56 carried by headbox 5a is connected to the crank lever 55. The jack screw 56 may be operated by power means (not shown) or by a hand wheel 57. When jack screw S6 is operated to raise or lower the connected end of crank lever I55 shaft 50` is rotated about its central axis. Rotation of the drive shaft 50 raises and lowers the connected end of the adjusting arm 26 about the pivot 31 and bends the upper lip 21 to vertically adjust the position of the slice opening end of the upper lip 21 relative to the lower lip 22.

In the operation of forming unit 1, a dilute stock having from about 1/2% to l%% fibers dispersed in 991/2% to 981/i% water, is discharged from slice opening 6 of headbox 5, into the nip N. As the belt 8 laps forming roll 7, with stock therebetween, water is squeezed from the stock and the dewatered stock forms a web of fibers. The belt 8 and web W are lifted from forming roll 7 by pickup roll 10 and the felt belt 8 carries the web W through such intermediate stages as may be provided and finally through the final stage forming unit 2 to the pickup press 3. The nuts 42 and 43 may be set so link 40 establishes a desired angular relationship between the sections 26a and 26b of each adjusting arm 26 for warping the upper lip to provide the upper lip with a desired profile. Rotation of drive shaft 50 raises and lowers the connected end of the adjusting arm 26 about the pivot 31 and bends the upper lip 21 to vertically adjust the position of the slice opening 6. As has been stated, because the pivot 31 about which the adjusting arm 26 turns is spaced well to the rear of the slice opening 6, and the drive shaft 50 is even farther to the rear, the nozzle and adjusting arm 26 can be made with a very low profile and small angle taper and the nozzle 20 therefore may be inserted deep within the nip N and close to the location where the felt belt 8 comes in contact with the forming cylinder 7.

From the foregoing detailed description of the present invention it has been shown how the objects of the present invention have been attained in a preferred manner. However, modification and equivalents of the disclosed concepts such as readily occur to those skilled in the art are intended to be included in the scope of this invention. Thus, the scope of the invention is intended to be limited only by the scope 0f the claims such as are or may hereafter be, appended hereto.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. In a headbox having a flow chamber connected to a tapered nozzle defining a slice opening for jetting paper stock from the flow chamber into a nip between a cylindrical forming roll and a felt tangentially engaging and lapping a portion of the forming roll, and said headbox having a first lip for projecting into such a nip adjacent such a roll and a second lip vertically spaced from the rst lip for projecting into such a nip adjacent such a felt, an improved adjusting mechanism for the second lip comprising:

(a) an adjusting arm connected on one end to an outer surface of the second lip proximate to the slice opening, projecting toward the ow chamber end of the nozzle and diverging from the second lip to define a generally wedge-shaped space between the arm and the second lip;

(b) a horizontal pivot connected to the arm intermediate the ends thereof;

(c) a journal connected to the pivot and having a link portion spanning the space between the adjusting arm and the second lip and connected to the second lip; and

(d) drive means mounted on the headbox and co-nnected to an end of the adjusting arm remote from the slice opening, and operative to raise and lower' the connected end of the adjusting arm about the pivot and vertically adjust the position of the slice opening end of the second lip relative to the first lip.

2. In a headbox according to claim 1, the drive means comprising a horizontal rotatable drive shaft mounted on the headbox adjacent an end of the adjusting arm remote from the slice opening with the shaft having a peripheral connection with the adjacent end of the adjusting arm; and means connected to the drive shaft for turning the drive shaft about a horizontal axis central thereof to raise and lower the connected end of the adjusting arm about its pivot and vertically adjust the position of the slice opening end of the second lip relative to the first lip.

3. In a headbox according to claim 2, the peripheral connection of the shaft to the adjusting arm being pro- 6 vided by a horizontal pin attached to the periphery of the shaft and projecting into a slot defined in the end of the arm.

4. In a headbox according to claim 1 the adjusting arm comprises a first and a second section pivotally connected by a horizo-ntal pin at a location between the journal and the drive means, one of said arm sections has a portion projecting around the pin and toward the flow chamber end of the arm with a terminal end of this portion vertically spaced from the other of the sections, and a vertically adjustable link connecting said terminal portion of the one section to said other of the sections to provide for holding the two sections in variable preselected angular positions relative to each other for warping the second lip to provide the seco-nd lip with a selected profile.

5. In a headbox having a vertical flow chamber connected to a curved and tapered nozzle defining a slice opening for jetting paper stock from the Aflow chamber along a path having both horizontal and vertical components and into a nip above a cylindrical forming roll and beneath a felt tangentially engaging and lapping an upper portion of the forming roll, and said headbox having an upper and lower lip for projecting into such a nip, an improved adjusting mechanism for the upper lip comprising:

(a) an adjusting arm connected on one end to the top of the upper lip proximate to the slice openingprojecting toward the flow chamber end of the nozzle and diverging from the upper lip to define a generally wedge-shaped space between the arm and the upper lip;

(b) a horizontal pivot connected to the arm intermediate the ends thereof;

(c) a journal connected to the pivot and having a link portion spanning the space between the adjusting arm and the upper lip and connected to the upper lip; and

(d) drive means mounted on the headbox and connected to an end of the adjusting arm remote from the slice opening, and operative to raise and lowel` the connected end of the adjusting arm about the pivo-t and vertically adjust the position of the slice opening end of the upper lip relative to the lower lip.

References Cited UNITED STATES PATENTS 2,717,539 9/1955 Metcalf 162-317 X 3,463,701 8/1969 Curtis 162-347 3,252,853 5/1966 Holt et al 162-317 X 2,162,097 6/1939 Metcalf 162-317 X 2,934,140 4/1960 Goodwillie 162-317 3,575,799 4/1971 Gedemer et al. 162-347 S. LEON BASHORE, Primary Examiner R. H. TUSHIN, Assistant Examiner U.S. Cl. XR. 162-299, 347 

